The National Reporting and Learning System (NRLS) collects data on national patient safety incident reports that are voluntarily and anonymously reported by staff working in the National Health Service (NHS) and other healthcare organisations in England and Wales. The reports include incidents and near misses. The report template allows the input of categorical data (e.g. incident type and location) as well as free text fields that allow staff to describe the incident, its perceived causes and the actions taken. Incidents within the database are classified by the reporter as having been linked to death, severe harm, moderate harm, low harm or no harm.

These data describe medication errors reported to the NRLS from 1st January 2016 to 31st December 2021, that might be associated with difficulties finding or understanding information in clinical guidelines. They includes details of the context of each incident (e.g. location, clinical speciality, drug involved) and additional coding of free-text variables (now redacted) showing whether the incident was related to difficulties finding or understanding information in clinical guidelines.